JPH02157199A - Metal mold for single crystal forming substrate and single crystal substrate using same - Google Patents

Abstract

PURPOSE:To obtain the metal mold at a low cost by forming a rectangular wavy, dotted or saw-toothed lattice on a superalloy or cermet contg. WC or Cr8C2 and coated with an Ir alloy film. CONSTITUTION:The surface of a superalloy or cermet 11 contg. WC or Cr8C2 is mirror-polished and coated with an Ir alloy film 12 by sputtering. An electron beam resist 13 is applied to the film 12, prebaked, irradiated with electron beams and developed. The film 12 is then etched with ion obtd. by electron cyclotron resonance through the resist and this resist is removed. A metal mold for a single crystal forming substrate having a rectangular wavy, dotted or saw-toothed lattice is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a mold and a glass substrate for producing a glass substrate used for forming a single crystal of a magneto-optical material, a semiconductor material, a superconducting material, etc. formed on top.”
The present invention relates to a single crystal film (single crystal substrate) of the material listed in item 1.

2. Description of the Related Art As a conventional method for producing a thin film single crystal, for example, in the case of silicon, a silicon thin film is formed on a silicon single crystal substrate by an epitaxial method. Regarding garnet thin films, which are magneto-optical materials, single-crystal garnet film is deposited on a single-crystal gadolinium-iron-garnet (GGG) substrate using a liquid phase epitaxial method (LPE method).
l membrane has been created. In superconductors, a bismuth-strontium-calcium-copper-oxygen single-crystal thin film is formed on a magnesium oxide (MgO) single-crystal substrate. Regarding silicon, attempts have also been made to create a single crystal thin film by providing a rectangular wave structure lattice on an amorphous substrate and depositing silicon thereon.

(For example, D, C, Flanders, and H, 1,
Smith: App 1. physLe
tt, 32 (1978) 112) Problems to be Solved by the Invention When trying to create a single crystal thin film of various types (Si, Garneno, superconducting, etc.), conventionally, as a base substrate,
It has the disadvantage that an expensive single crystal substrate (for example, 5IGGC, MgO, etc.) is used, and epitaxial growth must be performed on the substrate at a high temperature.

Regarding silicon, an amorphous S + 02 substrate is used as the base, but in order to create a rectangular wave structure on the substrate, it is necessary to draw the resist pattern one by one and perform reactive ion etching. Moreover, it involves an expensive and complicated process in producing the substrate, and has the drawback of extremely low productivity.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention fabricates a rectangular wave-like, lattice-dot-like, or sawtooth-like lattice by photolithography on WC or cermet coated with an If alloy film. A mold is prepared, and using this mold, a glass substrate for forming a single crystal (a glass substrate in which a lattice shape is formed on the glass substrate by a heating compression molding method) is manufactured with high productivity and at low cost. Moreover, a single crystal film of silicon, garnet, or a superconductor is formed on a glass substrate having this lattice shape by chemical vapor deposition (CVD).

Effect of the present invention: A glass material (amorphous material) is heated and press-molded using a mold having a pair of lattice shapes (rectangular wave shape, lattice dot shape, sawtooth shape), just like press molding of a record disc. This is a method of forming a lattice shape (photolithography is used to create the mold, but the mold is
(If you create a set, you can transfer the lattice shape onto the glass material as many times as you like.) With fewer manufacturing steps, you can expect to improve productivity.

Furthermore, on an amorphous substrate having such a lattice shape, CVD
When various materials are deposited using this method, thin films with orientation according to the lattice shape grow, and these eventually become single crystals.

EXAMPLE Hereinafter, a single crystal forming substrate mold according to an example of the present invention and a method for manufacturing a single crystal substrate using the mold will be described with reference to the drawings.

Example 1 An example of the present invention will be described below with reference to FIG. 1st
[As shown in F(a), first, a 10 mm square and 3 mm thick
After polishing the cemented carbide base material whose main component is WC to a surface roughness of RMS=8 to 10, an iridium alloy film (Ir- Rh) was formed into a film with a thickness of 3 μm by sputtering.

Next, as shown in FIG. 1(C), an electron beam resist (PMM) is applied.
A) was applied to a thickness of 1,000 mm, prebaked, and then irradiated (exposed) with an electron beam so that a lattice-like groove of 0.5 μm in the pinch and 0.25 μm in the line was formed [Figure 1 ( d). After development [Fig. 1(e)], the iridium alloy film was etched to a depth of 700 nm in argon (Ar) gas by electron cyclotron resonance (ECR) ion etching [Fig. 1(f)]. ] After that, the unnecessary resist was removed and lattice grooves (pinch width 0.5 μm, width 0.25 μm, depth 0.07 μm) were formed to create a substrate mold for single crystal formation [Figure 1 (g)] . Iridium alloy is Ir-Pt,
A substrate mold for forming a single crystal was also created using the same method for Ir-0s Ir-Re.

Example 2 An lr alloy film (Ir-Pt film) was deposited on a 10-mm square, 3-mm-thick samen 1 base material whose main component was titanium carbide (T i C), which was mirror-polished in the same manner as in Example 1. A film with a thickness of 3 μm was formed using the Svanta method.

Next, an electron beam resist was applied to a thickness of 2,000 mm, and after prebaking, an electron beam resist was applied with a pitch of 1.0 μm and a thickness of 0.5 μm in the line.
The resist was irradiated with an electron beam to expose the resist so that a lattice groove of μm size was formed on the resist.

After developing the second resist, the resist is removed using ion etching in a mixed gas of argon gas and CF4 to form a sawtooth pattern (ion irradiation angle: 45 degrees) as shown in Figure 1 (h). A substrate mold for forming a single crystal was created [Figure 1 (j)].

Example 3 In the same manner as in Example 1, I was deposited on a 10 mm square, 3 mm thick mirror-polished cemented carbide whose main component was chromium carbide.
After forming the r-alloy (Ir-Re alloy film), a resist is applied, and a 1 μm square mask (light-shielding )
After preparing a photomask (a photomask made of Cr on glass or quartz) and transferring the mask pattern onto the resist using the ultraviolet exposure method [Figure 2 (b)]
The resist is developed and then irradiated with an argon ion beam.
The r-alloy was etched to a depth of 600 mm, and a lattice-shaped pit (
A mold for forming a single crystal was prepared with a 1 μm square and a depth of 600 mm.

Example 4 Example (4) of the present invention will be described with reference to FIGS. 3 and 4. Substrate mold for single crystal formation created in Example (1) (
Prepare two sheets of lattice-shaped skumpers (one of them may be a flat surface of WC without lattice-like grooves), and as shown in FIG. A
A glass plate (10 mm square, 3 mm thick) consisting of 2% by weight of l2O2 and 12% by weight of B2O3 was inserted between the scoopers and heated to 800°C while applying pressure of 2 kg.
/CIfl) After cooling, the glass plate was taken out.

Next, the process of forming a garnet single crystal film using a glass substrate with grooves in the lattice shape (single crystal forming substrate, FIG. 3(b)) will be described with reference to FIG.

FIG. 4 shows a schematic diagram of an ECR plasma CVD apparatus. In the figure, 41 is a plasma chamber for generating high-density plasma for ECR, 42 is an electromagnet that supplies the magnetic field necessary for ECR, 43 is a reaction chamber, 44 is a microwave (2.45 GHz) inlet, Reference numeral 45 is an inlet for a gas serving as a plasma source, 46 is a base substrate (substrate for forming a single crystal), and 47 is a substrate holder, which enables heating of the substrate.

48.49, 50.51 are vaporizers containing raw materials, 52
is an inlet for carrier gas (N2).

53 is an exhaust port connected to a pump (a turbomolecular pump or a diffusion pump) for forcibly evacuating the reaction chamber.

First, the inside of the plasma chamber 41 and reaction chamber 23 was 4×107T
The pressure is reduced to orr to remove adsorbed gas, etc.

Next, oxygen (flow rate 20 cc/min), which becomes a plasma source, is introduced into the plasma chamber 41 from the introduction port 45, and from the introduction port 44,
By applying 500 W of 2.45 GHz microwave and setting the magnetic field strength to 875 Gauss using an electromagnet, E
Generate CR plasma.

At this time, plasma generated by the divergent magnetic field by the electromagnet 42 is drawn out from the plasma chamber 41 to the reaction chamber 43. In addition, iron acetylacetonate, bismuth acetylacetonate, isotria dipyhaloid methane, and aluminum acetylacetonate were placed in vaporizers 48, 49, and 5051, respectively, and heated to 130°C and 120°C, respectively.
The vapor was introduced into the reaction chamber 43 together with a nitrogen carrier (flow rate of 1.0 cc/min each) and flowed onto the substrate 46 heated to 500°C for about 30 minutes. Made it react. The degree of vacuum during film formation is
The pressure was 1.9 x 10'4 Torr.

As a result of analyzing the obtained film, the film composition was found to be i2゜Yo,s
FC3,8Aff+, z > 2, and had a garnet-type single crystal structure.

Next, the Faraday rotation angle at a wavelength of 780 nm was measured and found to be 4.1 deg/μm. The results are shown in Table 1 Sample No. 1. Garnet single crystal films were similarly created using other metal compounds or by changing the single crystal forming substrates obtained in Examples 2 and 3. The results are shown in sample numbers 2 to 5 in Table 1.

(Hereafter, extra white) ■ Example 5 Embodiment 5 of the present invention will be described with reference to FIGS. 3 and 4.

Two single crystal forming substrate molds (serrated stampers) prepared in Example 2 are prepared (one of which may be a flat type without serrated grooves), as shown in FIG. 3(a). Composition is SiO
□73% by weight, Na2O is 16.5% by weight, A#! 20
A glass plate (10 mm square, 3 mm thick) consisting of 1% by weight of 3, 5% by weight of CaO, and 3.5% by weight of MgO was sandwiched between stand bars and heated to 780°C while pressurized. After cooling (pressure: 2 kg/crM), the glass plate was taken out.

Next, a glass substrate with this sawtooth groove [Fig. 3(b)]
The process of forming a superconducting single crystal film using a single crystal forming substrate will be described with reference to FIG.

FIG. 4 shows a schematic diagram of an ECR plasma CVD apparatus. In Fig. 4, 41 is a plasma chamber for generating high-density plasma for ECR, 42 is an electromagnet that supplies the magnetic field necessary for ECR, 43 is a reaction chamber, and 24 is a microwave (2,450+-1z). An inlet 45 is an inlet for a gas (oxygen) serving as a plasma source, 46 is a base substrate (substrate for forming a single crystal), and 47 is a substrate holder, which enables heating of the substrate. 48, 49, 50, and 51 are vaporizers containing raw materials, and 42 is an inlet for carrier gas (N2). 43 is an exhaust port connected to a pump (turbo molecular pump or diffusion pump) for forcibly evacuating the reaction chamber.

First, the inside of the plasma chamber 41 and reaction chamber 43 was 4×107T
The pressure is reduced to orr to remove adsorbed gas, etc.

Next, oxygen (flow rate 20 cc/min), which becomes a plasma source, is introduced into the plasma chamber 41 from the introduction port 45, and from the introduction port 44,
By applying 500 W of 2.45 GHz microwave and setting the magnetic field strength to 875 Gauss using an electromagnet,
Generate ECR plasma. At this time, the plasma generated by the divergent magnetic field by the electromagnet 42 is drawn out from the plasma chamber 41 to the reaction chamber 43, and is also drawn out from the vaporizers 48, 49,
Copper dipivaloylmethane [C11 (
CIIHI902)2) , Calcium dipivaloy)'
vj tough 1: ca (CIII11902) 2) l
Strontium dipivaloylmethane (Sr(CzH+q
O□)2 Bismuth dipivaloylmethane (Bi(C++H
+qO□)3] and heated to 105°C, 1
It is heated to 30°C, 135°C, and 100°C, and its vapor is introduced into the reaction chamber 43 together with a nitrogen carrier (flow rate of 1.0 cc/min, respectively). By bringing the introduced vapor into contact with active plasma drawn out from inside the plasma chamber 41, a reaction was carried out for 60 minutes, and a film was formed on the glass substrate 46 having sawtooth grooves.

Note that the substrate temperature during film formation was constant at 400'C. The degree of vacuum during film formation was 3.5 x 104 Torr.
Met.

Analysis of the obtained film revealed that it has a perovskite single crystal structure, and the superconducting transition temperature measured by the four-terminal method is 12
It was at 4°.

The results at this time are shown in sample number 1 in Table 2. In the same manner, the analysis results of the membrane and the superconducting transition temperature when the material (evaporation raw material) put into the vaporizer was changed were calculated from sample numbers 2 to 2 in Table 2.
Shown in 3.

Effects of the Invention As described above, according to the present invention, a substrate for producing a single crystal (a substrate with lattice grooves) can be produced with extremely high productivity, and if this substrate (made of glass) is used, This is an extremely useful invention industrially, since a single-crystal film and a single-crystal substrate can be obtained without using such an expensive single-crystal substrate.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the manufacturing process of a mold (stamper) for creating a substrate on which a single crystal film will be formed, and Figure 2 is a cross-sectional view of the manufacturing process of a mold (stamper) for creating a substrate on which a single crystal film will be formed. Figure 3 is a cross-sectional view of the process of creating a substrate on which a single crystal film will be formed, and Figure 4 is a diagram of the manufacturing process of a mold for forming a single crystal film. 1 is a schematic diagram of an ECR plasma CVD device for [1] Base material (carbide, cermet) L12.
...Iridium alloy film, 13... Photoresist. Agent's name Patent attorney Shigetaka Awano To one person Decoy L'Fa @Iwaotsukudeqsaku Vkuta- 11' old map -cu o') 0) ~ ~ Ward Otsuqorb $

Claims (6)

[Claims] (1) Tungsten carbide (WC) coated with an iridium (Ir) alloy film, or a cemented carbide or cermet containing chromium carbide (Cr_3C_2) is formed into rectangular waves, lattice points, or sawtooth shapes by lithography. A mold for a single crystal forming substrate, characterized by providing a lattice of. (2) The iridium alloy film coated on the cemented carbide or cermet is an iridium (Ir)-platinum (Pt) alloy, an iridium (Ir)-rhodium (Rh) alloy, or an iridium (Ir) alloy.
- The mold for a single-crystal forming substrate according to claim 1, wherein the mold is one of an osminium (Os) alloy and an iridium (Ir)-rhenium (Re) alloy. (3) The mold for a single crystal forming substrate according to claim (1), wherein the lithography method is an electron beam lithography method. (4) A pair of molds provided with a rectangular wave, lattice point, or serrated grid is heated, glass is sandwiched between the pair of molds, and pressure is applied from above and below to the pair of molds. In addition, a single crystal forming substrate is obtained by transferring the lattice shape of the mold onto glass. (5) A single-crystal substrate in which a garnet single-crystal film is provided by chemical vapor deposition (CVD) on a substrate provided with a rectangular wave, lattice point, or sawtooth lattice. (6) Copper (C
u) - Calcium (Ca) - Strontium (Sr) -
Oxygen (O)-M [where M is bismuth (Bi), lead (
Pb) Any element among thallium (Tl)]
A superconducting single crystal substrate with a system single crystal film.